import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static String setstring(String str) {
        // write code here
        int i = 0;
        String result = "";
        for (i = 0; i < str.length(); i++) {
            char ch = str.charAt(i);
            if (!result.contains(ch + "")) {
                result += ch;
            }
        }
        return result;
    }

    public static String setstring2(String str) {
        // write code here
        int i = 0;
        StringBuilder result = new StringBuilder();
        for (i = 0; i < str.length(); i++) {
            char ch = str.charAt(i);
            if (result.indexOf(ch + "") < 0) {
                result.append(ch);
            }
        }
        return result.toString();
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        while (scanner.hasNextLine()) {
            String str = scanner.nextLine();
            System.out.println(setstring(str));
        }

    }
}
